Process and apparatus for treating sewage or other organic matters



June23, 1931. A. 'r. MALTBY A 1,311,131

PROCESS AND APPARATUS FORTREATII Q'G SEWAGE OR OTHER ORGANIC IATTERS Filed 001'.- 20. 1928 iyri Patented June 23, 1931 UNITED STATES PATENT OFFICE ARTHUR T. MALTBY, OI CHICAGO, ILLINOIS PROCESS AND APPARATUS FOR TREATING SEWAGE OR OTHER ORGANIC MATTERS Application filed October 20, 1928. Serial No. 313,845.

My invention relates to improvements in the biologic process for the treatment of sewage, or'other water borne organic matters, in which superficial areas supporting bacterial growths, called contact beds, are brought in contact alternately with the treated liquor and the atmosphere, the liquor being subjected to the activities of the bacterial growths for the purpose of disintegrating, nitrifying,

' and mineralizing the organic content therein,

while at the same time preventing, so far as practical, any putrifactive tendency of the organic content of said liquor both during and after treatment.

Ihe organic content of a contaminated liquid usually occurs in two characteristic physical conditions, namely: the insoluble and undissolred, chiefly carbon, elements, which are carried in suspension, and the soluble lique- 2 tied, chiefly nitrogen, elements carried in solu tion.

- The disintegration of dead organic matter by bacteriais carried on-in two progressive stages namely: carbon and nitrogen fermentations, each of which may be subdivided into first and second carbon and first and second nitrogen fermentations respectively.

There are two general types of bacteria which effect the disintegration of organic matter, namely: the anaerobic type, which thrive and operate in the absence of air, and the aerobic type, which thrive and operate in the presence of air.

Anaerobic fermentations are productive of putrifaction, ofi'ensive odors, and unsightly conditions, and are effective in the initial, or

' first carbon, fermentations only, the latter three necessarily being aerobic. Aerrbic fermentations do not cause putrifaction or ofiensive odors, and are therefore preferable, but-none of them will function while subject to the effects of anaerobic activities, and also the latter three, which are harmonious, will not take place while the initial or rectifying aerobic fermentation is in progress. unless segregated.

\Vhen the velocity of flow of the liquid is retarded, or becomes quiescent, more or-less of the unfermented suspended matters will I settle out and accumulate wherever lodgement is found, thereby setting up anaerobic fermentation to the detriment of aerobic functions.

The fundamental necessity of aerobic fermentation is to subject the organic matter to theaction of bacteria in the intimate presence of oxygen and moisture at one and the'same time. The oxygen may be as dissolved air in the liquid, to be renewed by periodic exposure to the atmosphere, or air and capillary moisture, as in the soil betweenrai'n storms in nature.

The effect of aerobic first carbon fermenta tion is to release various gas and liquid elements, leaving a black, sticky, residue called humus which has the faculty of adhering to metallic and other substances. Under more or lessconfined conditions as in a filter, the various suspended, floating and colloidal matters, undergoing initial fermentation, will prevent aerobic functions, and will accumu- 7 late and clog the openings, excluding air, with consequent putrifactive effect. It is therefore necessary to remove the suspended matters before applying the liquid to a filter.

Humus is however, the natural and seemingl-y necessary environment for aerobic bacterial life, and under proper conditions of distribution, drainage, and aeration, will undergo secondary fermentation, the greatly re duced final residue becoming nonputrescible.

A general object of the present invention, is to produce an improved process for treating sewage or other liquid organic matters, which operates exclusively through activity of bacterial growths of the aerobic type.

A. further object is to provide apparatus arranged to carr out and accelerate both the carbon and nitrogen fermentations of liquid borne organiomatters, in one progressively continuous operation by; means of aerobic bacterial growths.

A further object is to provide apparatus arranged to thoroughly distribute and thereby bring about intimate contact between the 5 organic matters and the bacterial growths, in the presence of air and moisture, and at the same time prevent lodgement or accumulation of unfermented organic matters to the extent of causing anaerobic fermentations 1:-

and consequent interference with normal aerobic functions.

' A still further Object is to provide openly exposed areas of such arrangement and extent, as will retain and carry the normal deposits of humus and aerobic bacterial growths, without congestion, and provide for aerating the same'during intermittent periods.

A further characteristic of the invention, resides in a mechanism and process of the character referred to, which operates on the fill and draw principle, as well as the continuous flow method. I

These objects I accomplish by the use of a biologic wheel having a central axle arranged to revolve in bearings mounted upon opposite side walls of a conduit or pit, into 'which the lower part of the wheel projects:-

by the use of transverse plates and discs located in the body of the wheel, said plates and discs designed to provide surface area to which humus and the necessary bacterial growths may adhere and form contact beds, and the plates and discs so arranged that the wheel may be caused to revolve by force of theflowing liquor through the conduit, or be driven by other sources of power as desired; by the use of a plurality of wheels arranged in series in a conduit the liquor flowing by gravity through one wheel to another until the required retention period of treatment is obtained; and by the use of a tank with one or more wheels which are caused to revolve by extraneous power until the required retention period of treatment is obtained. v

These and other objects and features of the invention will appear more fully from the following detailed description when read in connection withtheaccompanying drawings, and will be pointed out in the appended claims.

The invention is illustrated by the accompanying drawingsin which F ig. 1 is a side elevation with portions of the side wall of the tank and wheel pits removed showing arrangement and position of the wheels inrelation to the tanks, the liquor, and to one another. Fig. 2 is a cross section of the wheel pit and wheel on the line 22. v

' In the drawings, the numerals indicate the various parts throughout the various views.

A rectangular tank, constructed of concrete or other suitable material, is divided by the weirs (1) and (2) into three compartments, viz, the precipitation, or grit, chamber, in which the heavy and inorganic substances are separated from the incoming liquor, the digestion chamber (4) in which the liquor is subjected to the action of the bacterial growths carried by the contact beds, and the sedimentation tank (5) in which the residual sludge is allowed to settle out of the treated liquor, the efiluent passing over the adjustable weir (6), which regulates the rate of flow through the series of chambers.

One or more biologic wheels (7) isassociated with the digestion chamber (4). The wheels .are so positioned in respect to the digestion chamber and the level of the liquid therein, that substantially the lower half of the wheel will be submerged in the liquid.

upon which the plates or d-iaphragms (l3) and the discs (14) are carried. A plurality of transverse dipper plates (15) are located transversely across the periphery of the wheel, the open side in the direction of flow. The plates and discs serve to accumulate pagterial growths thereby. forming contact .Each Wheel (7) is mounted above a wheel pit (16) the surface of which is circular to conform to the curvature of the wheel periphery and this curved are is wiped by the drag chains (17) located upon the periphery of the wheel. From the top of the down stream end of the said curved sector, the tank bottom (18) slants down to the succeeding wheel pit thus preventing accumulations of sludge.

It will be seen that the basic principle of this improvement is the employment of movable contact beds and removing the beds from the liquor (instead of removing the liquor from the bed) for aerating and rejuvenating purposes, thus facilitating the use of the continuous flow principle.

It will also be seen that as the bacterial growths accumulate, the entire exposed surfacg1 of the Wheel will become activated therewit It will also be seen that the transverse plates by obstructing the passage of the flowing liquor through the wheel pit will cause the wheel to revolve thereby causing the activated contact beds to be alternately immersed in the liquor and aerated in the atmosphere.

The transverse plates divide the wheel into segments which become filled with the liquid during the rotation of the wheel. The liquid entrapped within each segment is reversed during its passage through the wheel, that is to say, the plateconstituting the bottom of the segment on the inlet side, becomes the top of the segment on the outlet side of the wheel thereby exposing the lower strata of the liquid to the atmosphere. The wheel rotates at the same velocity as the flowing liquid thereby producing a condition of relative quiescence between the liquid and the moving plates during the submerged period. However in spite'of the fact that the li uid is not agitated, or rather in view of tat fact, the liquid and its contained matter will be brou ht into intimate contact with the bacteria growths and air by reason of being distributed broadly across the transverse plates on the wheel and thus subjected to, and inoculated with, thebacterial growths thereon. Consecutive aerobic fermentations are brought about in this manner.

It will also be seen that as the sludge settles out of the li nor in each segment, during its passage rough the wheel, it will generall fall u on one of the activated contact bedf; and subjected thereto during the submerged and aerating period, and that such portion of the sludge as may fall from, or between the beds will reach the curved sector of the wheelpit and be carried along, or be broken up by the wiping chains on the wheel periphe It will also be seen that the dippers will carry a volume of air to the bottom of the wheel pit where it is automatically. released to float u ward to further aerate the liquid entrappe within a submerged segment.

It WlllfllSO be seen that the circular discs divide the segments into longitudinal slots thereby providing additional surface area for accumulating baterial growths and also serve to lar ely replace the transverse plates when the w eel is driven by power other than the flowing liquid.

What I claim is:

1. Apparatus for treating sewage or other liquid organicmatters including a rotor provided witha plurality of radially disposed transverse plates carrying bacterial growths, and a container for the liquid the lower portion of the container formed as a circular transverse pit the curved surface of which is arranged to receive and closely conform to the curve of the wheel periphery and the wheel positioned and caused to rotate in said.

' container with the lower portion of the wheel periphery moving in close relation to the curved surface of the pit and in such manner that the bacterial growths are periodically submer ed in the liquid and exposed to the atmosp ere.

2. Apparatus for treating sewage or other hquld organic matters, including a rotor pro vided with a plurality of transverse and circular platesca bacterial growths and a container for the liquid the lower part of the container formed as a circular transverse pithaving a curved section arranged to receive and closely conform to the curveof the rotor riphery and the rotor positioned and 'cause 'to rotate in the container in such manner and relation that. the bacterial growths carried in said rotor are periodically radially disposed transverse p ates carrying bacterial growths and a container holding a liquid the lower portion of the container formed as a transverse it having a curved section arranged to con ormto the curve of the wheelperiphery and the wheel positioned and caused to rotate in said container with the lower portion of the wheel periphery movin in close relation to the curved surface of sai pit in such manner that the lower portion of the wheel is submerged in the liquid in said pit and the upper portion exposed to the atmosphere.

4. Apparatus for treating sewage or other liquid organic matters including a series of biolo ic wheels divided into segments b radially disposed transverse plates which serve to carry bacterial growths and a tank through which the liquid flows the lower portion ofthe tank formed as a series of transverse circular pits the curved surfaces of which are arranged to receive and closel conform to the curve ofthe wheel perip cries and the wheels positioned and caused to rotate in said tank with the lower part of the wheel peripheries moving in close relation to the curved surfaces of the pits and in such manner that the bacterial growths are alternately submerged in the li uid in said pits and exposed to the atmosp ere.

5. Apparatus for purifying) sewage or other liquid organic matters y aerobic bacterial fermentations said apparatus including a rotary biologic wheel rovided with transverse plates carrying acterial growths and a container for the i uid the lower portion of the container forms as a transverse circular pit arranged to receive and closely conform to the periphery curve means of 4m of the wheel and the wheel positioned and. caused to vrotate in such manner that the lower part ofthe wheel periphery will move in close relation to the curved surface of the pit thereby preventing the accumulation of organic sediment therein the rotation of the' owths and acontainer through which the v x iquid flows, the lower part of the container formed as a transverse circular pit arranged to'receive and closely conform to the curve' I of the wheel'peri hery and the wheel positioned and cause part of the wheel periphery in close relation to the curved surface in said pit and in such manner that said transverse plates are to rotate with the lower.v

caused to move at the same average velocity up as the flow of the liquid through the pit thereby maintaining a condition of quiescence relative to the liquid and the moving bacterial growths carried on said plates.

7. Apparatus for purifying sewage or other liquid organic matters including a rotor provided with transverse plates carrying bacterial growths and a container throu. h which the liquid flows the lower part of t e container formed-as a transverse circular pit arranged to receive and closely conform to the peripher curve of the rotor and the rotor positione and caused to rotate in the container in such manner that the lower part of the rotor periphery will move in close relation to the curved surface of the pit the rotation of the rotor causin the bacterial owths to be alternately sufimerged in the iquid and exposed to the atmosphere whereby the incomin li uid is continuously inoculated with aero ic acterial growths derived in the container and the lower from said bacterial growths carried in the rotor.

8. Apparatus for purifyin sewage or other liquid organic matters inc uding a rotary biologic wheel divided into transverse segments by radially disposed transverse lates and the segments also divided longitu inally by circularly disposed plates the said plates carryin bacterial growths and a container for the i uid the lower portion of the container forme as a transverse circular pit conforming to the curve of the wheel periphery and the wheel positioned and caused to rotate in the container in such manner and relation that the bacterial growths on said container so arranged that the lower edge of the aforesaid transverse plates will move in close relation thereto in such manner that unfermented organic sediment accumulations are prevented and the bacterial ..owths are periodically submerged in the liquid in the container and exposed to the atmos here.

ARTHUR T, MALT Y.

plates are alternately submerged in the liquid in said pit and exposedto the atmosphere.

9. Apparatus for treating sewage or other liquid organic matters including a rotary biologic wheel divided into segments by radially disposed transverse plates carryin bacterial growths and a container throng which the liquid flows the lower portion of the container formed as a transverse circular pit arranged to receive and closely conform to the wheel periphery andthe wheel ositioned with t e axle above the liquid evel part ofthe wheel periphe .in close relation to the curved surface 0 the pit in such manner that the plates obstruct the flow of the liquid causing said liquid to pass through the submerged segment divisions of the wheel and be s read broadly across the transverse faces 0 said plates as the wheel revolves thereby exposing the liquid and the organiccontent therein to 'nism provided with spaced apart transverse the bacterial growths carried on said plates.

10. Apparatus for treatin sewage or other liquid organic matters inc uding a mecha plates arranged and caused to move with their faces forming openly exposed surface a cteriel growths and areas for an portin i fiquid the bottom of the a container or the 

